This is my answer to a Quora question,
Here goes, the answer:
Madhwacharya condemned Advaitha preachers voraciously.
As a result majority of Brahmins converted back to Dvaita philosophy, mainly in karnataka and maharashtra.
Here are some shlokas of Harivayu Stuthi, where it is said Madhwacharya’s arguments were like roar of a lion which silenced the arguments of Pashandavadi.
Why was Madhwacharya so much against Advaitha Vadis?
You and me who are mere below average mortals can’t understand what goes in eminent people’s mind. Madhwacharya thought Advaitha is destroying the moral fibre of society. And such a strong opinion was perhaps required for establishment of kingdoms like Vijayanagar and Marathas under the guidance of able Gurus.
Shankaracharya said the entire creation is Maya.He said world is illusionary like a rope imagined to be a snake in midnight, he said Paramatma and Jeevatma are like mud and pot, contents are same but presented differently. He said God is attributeless, but his illusionary world is full of attributes because of Maya.
Even Buddha taught something similar – Shoonyavada. However unlike Buddha, Shankaracharya used Vedas, Upanishads and Bhagavadgita as references to prove Mayavada. This was not acceptable to Madhwacharya. He was furious because many people had accepted Advaitha and slowly people were becoming nihilistic.
In many books and arguments he proves that Shankaracharya’s arguments won’t go well with Vedas and Upanishads. For example,God himself came and taught Gita. He said karma never attaches to him but is applicable to all others. Many many similar shlokas are there that tell that there is distinct God and distinct Jeeva. And none of these are magic, universe is real, world is real, and the creator is real.
The acknowledgement of a real world and panchabedha of objects is very important to accept differences. Otherwise people will try to see uniformity everywhere while non uniformity is the rule of the world, Taratamya(Difference) is Jaganiyama (Universal Rule)
Note1: I just presented my thoughts on why Madhwacharya used such strong words to oppose Shankaracharya. I respect both of them a lot. Both of them revived hinduism in their respective periods. Both have contributed immensely to Hindu philosophy. Please don’t take offence to this answer of mine.
Note2: I wanted to add this second note for better clarification. Condemnation doesn’t mean defamation. No one, not even Madhwacharya defamed Shankaracharya personally. The attack was on philosophy through refutation of arguments.
Note3: This an answer to a comment that says why Advaita is immoral.
Advaitha talks about Paramarthika Sathya and Vyavaharika Sathya. All shritis/smrits are part of Vyavaharika Sathya and there it approves of worshiping God and that’s how we have got such wonderful compositions by Shankaracharya himself, but it also says it is not the absolute reality.
Reality is the only truth which is common across all three states, – Nidra, Swapna and Jagrata, and is called the fourth state or Turiya.
That being the case people are free to adapt anything in their Vyavaharika Achara. This makes people nihilistic.
Also Madhwacharya was not against Bhamati which also favoured Advaita, because it was only advaitavada not mayavada.
When Brahma is Satya and everything else is Mithya, the question is who originates Mithya.
Shankaracharya says Brahma only is the originator of this Maya, but Vachaspathi Mishra says, Maya has its origin in Jiva. If Jiva originates Maya, Jiva itself cannot be Maya and hence Real and hence is somewhat in sync with Dvaita.
Also to explain more when Maya has its locus in Brahma, Brahma cannot be Nirguna, in fact he has to be opposite of “Sat” to have created Mithya.
If Maya is attributed to Jiva, Brahma is rendered Saguna and hence Poorna. Jiva is attached to Maya because of Avidhya. One who knows Poorna is Poornapragna and hence the best among the Jivas. That’s why Madhvacharya is also called Poornaprajna.